Fire prevention devices for interrupting the electrical circuit in a motor vehicle on impact are known in the prior art. These devices include a variety of switching mechanisms. For example, Pernet--U.S. Pat. No. 3,466,409--shows a ball and spring circuit breaker; McCartney--U.S. Pat. No. 4,000,408--shows a cam and spring mechanism; Lacey--U.S. Pat. No. 3,406,774--shows spring loaded switches; Smythe--U.S. Pat. No. 2,304,608--shows a bridge disk and spring mechanism; Rossel et al.--U.S. Pat. No. 4,308,438--show a ball and socket rocker mechanism.
It is a problem with all these prior art systems, however, to carefully control the switching system to operate only at a predetermined impact, which comes from a collision of significant enough impact force to cause danger of fire.
An object of this invention therefore is to provide a certain and sure metering of impact magnitude in a fire prevention safety switching system for an automobile.